Wood-bending machine



Dec. .2, 1930. c. w. ELLIOTT WOOD BENDING MACHINE Filed March 11, 1927 2ShetS-Sheet 1 Dec. 2, 1930. c w LLo WOOD BENDING MACHINE Filed March 192z'sheets-sheet 2 Patented Dec. 2, 1930 PAT NT OFFCE N GHAItIiSw(iiLIQrouuJ,` oFsEYMoUR NDIANA i wooD-BENnmGM CHI E VApplicatonfiledvMarch 11, 1927. serial No. 174533.

i This* invention relates to machines for bending wooden strps such asare used in; the

manufacture of orchestra and band drum shells,' automobile 'wheel rims,chair-rockers molding and the like. V

It is my primary aim to generally improve upon-prior patented andmarketed machines of this class, but more particularly to improve upon'my prior -Patents Numbers o %0,525 and 1,507g368. i' Constant use orthe "patented machines specifically named has conclusively shown thattheyare objectional in "several respects. First, it hasbeen 'found thatin" bend ing comparatvely thick strips, slight beads or finsaresometimesformed'on the` inner side or" the curved product. secondlyg fit has been noted 'that where the grainin the strip is irregular orembodies knots', the

finished article would not b e perfectly true in shape. Moreover; sincethe wood is subjected to a heating-process during the bend-` ingoperation, it frequently straightens out somewhat 'and the bent'pieces'are not uni form in curvature. Thirdly, withthe ma chines of theprior art it is -impos'sible to bend a pieceof molding or other woodenmaterial having a transversely'beaded or curved sur-" face 'runninglongitudinallythereof, owing to the fact that the bending rolls tend toflatten or damage such surface.

e 7 With these defects inimind, I have now evolved and produced animproved structure which entirely 'overcomes theobjections, and uponconsidering the following de`scrip`tion,' the novel details and theirrelative arrangements,w ill become' clearly apparent.

I'would direct 'attention first to the ac companying drawings in whichFigure l is a top planvi ew of a machine constructed 'in ac'cordancewith the -present inventionp 3 I Figure`2'is a centralverticalfs'ection; Figure 3 is a 'perspective View ofthe traveling bedand its drive roller; s v

Figure 4 is a group perspective view of the adjustable pressei'` 'rolland work confining rings, disassembled;" i

Figure 5 is a `perspective detail View of a portion of oneof the'slatsor bed sections Figure 6 is a group perspective view oftheadjusting means of a work holding frame;

Figure 7 is a 'fragmentary longitudinal sectional view through theadjustable presser roll and showing the work confining strips in place;`i

Figure 8 is a cross sectional'view through th beddriving roller with thebed in place an i z i Figure 9 is a cross sectional view of a modifiedwork confining strip and a` piece ,of molding,` the strip being shapd toconform to the face profile of the molding to prevent in`-` jurytheretoin the bending operationL-- Referring now to thedrawing'sindetaiL it will 'be seen that the reference characters ldesignates a pair of duplicate supporting plates, which may, in practicebe fashioned to rest upon; an appropriate supporting-table or the like;-Mounted in suitable bearngs for rotation between the sideplatesare'three rollers'2, 3 and& respectively. As in the aforesaidpatents, these rollers are arranged in triangular relat ion, the roller2 being at the top, and the remaining rollers 3and 4 being in opposedand spaced parallelism beneath. The shaft of the roller 2, which isadjustably mounted in the manner shown'isprovided with a dr vng gear 5deriving its power from` any suitable source. Roller-4 isdriven by a'crossed belt 4 from pu'lley 2 on the shaft of roller' 2 and trained overa pulley l on the shaft of roller 4:. Roller 3 is an idler. I have alsoshown the patented arrangeinent 'of pip ing A for conducting a heatingmedium into certain oi' the rollers. Theseparts are all-old in thepatents and do not 'constitute the noveltv of thepresent invention i iThe firstimpro'ved detail to which I shall direct-attention is theendless bed 6 which surrounds the two bottom rollers 3 and 4. This bed&which iscomposed of transversely extending and -pivotally`connectedlinks or metal slatsg -is rather loo'sely mounted andisdriven'by roller&by means ofdepending slatjportijons G designed to engage in`longitudinal recesses 4cin the roller 4.- Thus, bed 6 moves with and conforms to the curve in 'which the'strip of Wood or work7 is bent by' the'rollers in 'the manner indicated in longitudinally spaced peripheralgrooves 8,

these being intended to receive sectional work confining rings 9 as seenmore plainly in Fig. 4. The rings are made in sections to permit easyapplication and removal, the sections being connected together in anyconventional way. In practice, any number of bands or rings 9 may beused, and here I might point out tha-t a separate bed 6 may be used inconjunction with each pair of rings, the bed being equal or preferablyslightly greater in width than the spaces between each pair. Thus, withthe aid of the bed 6, the work 7 may be adequately confined between apair of strips 9 to prevent for nation etthe objectionable iins at thesides from the pressure exerted by the rolls.

It has been theretofore stated that means is enbodied in theimprovedstructure to maintain the desired curvature of the Wood after ithas passed between. the main rollers. `While this means may be of someother design, it preferably comprises a pair of arms B pivoted as at B'to ears formed upon the Caps C' of the bearings C at either side of themachine and which support the shaft of roller 4.

Each of the arms B has two longitudinally spaced series of spacedhorizontal slots, designated at 10 and ll respectively. Slots 10 receivethe journal ends of small work holding rollerslO while slots llaccommodate the journals of similiar rollers ll. Set screws 12, 13working through the outer edges of arms B and in slots 10 11 act asadjustable stops for the journals or" the respective rollers 10, 11 sothatthe same may be located in a desired set position. It is understood,otcourse, that the work 7, on emerging from between the large bendingrollers 2, L, passes between the two sets of small holding rollers 10,11. Fhese rollers 10, 11 are so adjusted in spaced arcual series as tomaintain the work 7 in the longitudinally curved form produced by theaction of rolls 2, 3 and 4: and toprevent the work from straightening.

. While the range of relative adjustment of holding rollers 10, ll isample to suit the curve o't'the work in most instances I provide anadjustable connection between plates l and arms B whereby arms B maySwing inwardly or outwardly and beheld in a predetermned set position.Obviously this, with the roller adjustment greatly increases the rangeor degree of curvatureof the work that can be held by rollers 10, 11.The connection referred to comprises a pair of internally threadedtubular arms 14 pivoted to plates 1 as at 14 and receiving threadedbolts 15 which extend through hearing ears l6 at the upper ends of thearms B. Adjustment is had by applying a Wrench to the heads of bolts 15and turning the same.

A heavy pressure spring 17, suitably housed in each slotted bearing Cand adjusted by a set screw 17 bears against each journal of roller 4and tends to force the same away from roller 3, thus tending to maintainthe bed (5 tant and against the work 7 which is disposed'between thesame and the roller 2, In other words the bed 6 will, during theoperation of the machine, maintain its portion intermediatethe rollers 3and 4 in a true arcual. form which will vary' according to the curvaturegiven thework thus avoiding injury thereto.. As shown, the journal boxesof roller-2 are vertically slidable in slots 2 and are fioatinglysupported by heavy coil springs 2 Setting of roller 2 to produce adesired curvature of the work is Secured through set'screws 2 in aconventional manconcerns the present invention. The heated condition ofrollers 2, 3 greatly facilitates the bending operation,` However, in;the absence of the bend preserving rollers 10, ll then work in itsheatedstate would tend to straighteniout after passingfrom theheatedpresserrollers 2, 3. By the time the work hasipassed from between thesets of rollers 10, 11 it has cooled or set sufliciently to holditsshape. v

Figure, 9 illustrates a modified form of ring20 designed foruse in lieuof rings 9 When bendingmolding or other' longitudinallybeaded orornamentally ,grooved material. The outer portion of ring 20 is shapedto eX- actly conform to the beaded side oftheparticular molding 21 toibebent so as to avoid fiattening, chipping and damaging the same. In Viewof the` interfitting -or mating relationship of thecontiguous faces ofring 20 and molding 2l lateral stresses will; be distributedintermediate the side edgesof the latter and there will be no tendencyto. formtfins at the edges of the molding.

Of coursethere is no limit to the number of styles of beaded orornamentally faced molding that can be bent, it only being requisitethat a ring20 be used that exactly matches `the style of molding.

I claim z- I 1. A wood bending machine of the class described comprisinga plurality of rollers, bearings therefor, said rollers being spacedapart 'and arranged in triangular relation to permit the work to passtherebetween, the

uppermost roller being a driven roller, said upper roller having aplurality of longitudinally spaced grooves in its surface, and sectionalwork confining rings removably seated in said grooves.

2. A wood bending machine of the class described comprising a pluralityof roilers mounted in triangular relation and spaced from each other toallow the work to pass therebetween, the uppermost roller havingitssurface grooved, work confining rings seated in the grooves, anendless work contacting band surrounding the lower pair of rollers, andmeans arranged opposite the upper roller for coaction with the free end,

portion of the work to maintain the curvature of the same after it haspassed thru the triangularly disposed rollers, said means beingadjustably mounted and in the path of travel of said free end portion.

3. A wood bending machine comprisng a pressure roll, a former comprisinga pair of spaced pressure rolls, a flexible belt trained over saidspaced pressure rolls and comprisng transverse slats, said slats havinginterconnecting bearings by their longitudinal edges and provided with alateral cleat at one edge, one of said last-mentioned pressure rollsbeing driven and having longitudinal grooves a'dapted to receive saidcleats to drive said belt, bearings for said last-mentioned pressurerolls, and means for adjustably positioning one of said last-mentionedpressure rolls tovary the contour of said belt beneath saidfirst-mentioned pres sure rolls.

4. In a wood bending machine comprising a coactng former and pressureroll, the combination of a circumferential surface area of said rollhaving an irregular profile adapted to engage a correspondingly profiledsurface of a piece of work whereby through distribution of the lines offorce in a plurality of directions between the sdes of the work toprevent lateral spreading of the work under pressure.

5. In a wood bending machine comprising a coacting former and pressureroll, the combination of a plurality of peripheral rings carried'by saidroll, the latter having seating means for axiallyspacing said rings,said rings having their peripheries of irregular profile toengage acorrespondingly profiled surface of a piece of work whereby throughdistribution of the lines of force in a plurality of directions betweenthe sides of the work to prevent lateral spreading of the work underpressure.

In testimony whereof I afliX my signature.

CHARLES W. ELLIOTT.

